[stm32f429i-discovery] Merge and delete systick blink example.

Added Chucks improvements to the systick example into the ported one.
This commit is contained in:
Piotr Esden-Tempski
2015-01-22 15:51:20 -08:00
parent 7629bb01e6
commit c18a16d979
4 changed files with 7 additions and 124 deletions

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@@ -1,22 +0,0 @@
#
# This file is part of the libopencm3 project.
#
# This library is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this library. If not, see <http://www.gnu.org/licenses/>.
#
BINARY = systick-blink
LDSCRIPT = ../stm32f4-disco.ld
include ../../Makefile.include

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@@ -1,7 +0,0 @@
Systick Blink
-------------
This version of blink is slightly more sophisticated, it shows how you
can initialize the Cortex M SYSTICK register to give a regular interrupt.
It adds a function for doing precise delays. The original blink code
is then rewritten with this in mind to create a 10Hz blinking pattern.

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@@ -1,93 +0,0 @@
/*
* This file is part of the libopencm3 project.
*
* Copyright (C) 2013 Chuck McManis <cmcmanis@mcmanis.com>
*
* This library is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
/* This version derived from fancy blink */
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/gpio.h>
#include <libopencm3/cm3/nvic.h>
#include <libopencm3/cm3/systick.h>
/*
* Definitions for functions being abstracted out
*/
void msleep(uint32_t);
void clock_setup(void);
/* monotonically increasing number of milliseconds from reset
* overflows every 49 days if you're wondering
*/
volatile uint32_t system_millis;
/* Called when systick fires */
void sys_tick_handler(void) {
system_millis++;
}
/* sleep for delay milliseconds */
void msleep(uint32_t delay) {
uint32_t wake = system_millis + delay;
while (wake > system_millis) ;
}
/*
* clock_setup(void)
*
* This function sets up both the base board clock rate
* and a 1khz "system tick" count. The SYSTICK counter is
* a standard feature of the Cortex-M series.
*/
void clock_setup(void)
{
/* Base board frequency, set to 168Mhz */
rcc_clock_setup_hse_3v3(&hse_8mhz_3v3[CLOCK_3V3_168MHZ]);
/* clock rate / 168000 to get 1mS interrupt rate */
systick_set_reload(168000);
systick_set_clocksource(STK_CSR_CLKSOURCE_AHB);
systick_counter_enable();
/* this done last */
systick_interrupt_enable();
}
int main(void)
{
/* Set up clock and systick */
clock_setup();
/* Enable GPIOD clock. */
rcc_periph_clock_enable(RCC_GPIOG);
/* Set GPIO13-14 (in GPIO port G) to 'output push-pull'. */
gpio_mode_setup(GPIOG, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO13 | GPIO14);
/* Set LED for alternating effect when toggling. */
gpio_set(GPIOG, GPIO13);
/* Blink the LEDs (PD12, PD13, PD14 and PD15) on the board. */
while (1) {
gpio_toggle(GPIOG, GPIO13 | GPIO14);
/* Now sleep for 100ms which toggles at 10hz rate */
msleep(100);
}
return 0;
}

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@@ -46,7 +46,12 @@ static void msleep(uint32_t delay)
while (wake > system_millis);
}
/* Set up a timer to create 1mS ticks. */
/*
* systick_setup(void)
*
* This function sets up the 1khz "system tick" count. The SYSTICK counter is a
* standard feature of the Cortex-M series.
*/
static void systick_setup(void)
{
/* clock rate / 1000 to get 1mS interrupt rate */
@@ -57,7 +62,7 @@ static void systick_setup(void)
systick_interrupt_enable();
}
/* Set STM32 to 168 MHz. */
/* Set STM32 system clock to 168 MHz. */
static void clock_setup(void)
{
rcc_clock_setup_hse_3v3(&hse_8mhz_3v3[CLOCK_3V3_168MHZ]);